Byte Access Control; Figure 6.27 2-Cas Control Timing (Upper Byte Write Access: Rast = 0, Cast = 0) - Renesas H8S/2368 Series Hardware Manual

6.6.10

Byte Access Control

When DRAM with a ×16-bit configuration is connected, the 2-CAS access method is used for the
control signals needed for byte access. Figure 6.27 shows the control timing for 2-CAS access,
and figure 6.28 shows an example of 2-CAS DRAM connection.
Address bus
(
(
( )
Upper data bus
Lower data bus
Note: n = 2, 3
T
p
Row address
)
)
Figure 6.27 2-CAS Control Timing
(Upper Byte Write Access: RAST = 0, CAST = 0)
T T
r c1
Column address
High
High
Write data
Rev. 2.00, 05/03, page 163 of 820
T
c2
High-Z